Apparatus for making propellants of powder strands

ABSTRACT

Apparatus for making propellants of powder strands. A plurality of outer strands of the same length are first placed generally in the form of a bundle in an open-topped vertical receptacle. The bottom end of the receptacle is closed by a plate which may be withdrawn when the strands are to be allowed to fall into a strand-orienting fixture. The fixture is placed beneath the receptacle in alignment therewith, the fixture having a multiperforated upper plate with vertical, funnel-shaped openings therethrough which receive the lower ends of the strands therein when the combination of receptacle and fixture are vibrated, whereby to guide strands through such openings and downwardly into contact with a supporting plate. The powder strands in the embodiment shown are hollow. After all of such openings are closed by the upper ends of the forwarded strands, the receptacle is removed from the fixture, and there is applied to the upper end of the fixture a jig or second fixture carrying a plurality of spaced mandrels, when the strands are hollow, which are introduced into the upper ends of the hollow strands now positioned in the first fixture. The jig is provided with means whereby the mandrels grip the upper ends of the hollow strands sufficiently to support the strands. The second fixture is then removed from the first fixture, and the thus-oriented and supported strands are transported, in very accurately spaced position, for further treatment, such as drying, and ultimately to be introduced into the chamber of an explosive device. When the strands are not hollow, rings or sleeves may be substituted for the mandrels.

ietu

Gross States Patent [54] APPARATUS FOR MAKING PROPELLANTS OF POWDER STRANDS [72] Inventor:

[73] Assignee:

Gabriel Gross, Vichy, France Manufacture de Machines du Haut-Rhin, Mulhouse-Bourtzwiller, France 221 Filed: Aug. 3, 1970 21 Appl. No.: 60,600

[30] Foreign Application Priority Data Aug. 5, 1969 France ..69 26 815 [52] U.S. Cl ..269/51, 53/126, 53/246, 93/78, 93/93 HT, 102/99, 214/1 P, 269/52 [51] Int. Cl. ..B23q 1/10, B23q 7/04, 1365b 35/34 [58] Field of Search ..53/126, 240-248, 53/78; 93/93 HT; 214/1 P; 269/48.l, 50-52;

[56] References Cited UNITED STATES PATENTS 634,195 10/ l 899 Bidwell ..93/78 798,609 9/1905 Lassig 53/246 2,344,087 3/1944 Hetz ..53/247 2,691,817 10/1954 Rainone 269/52 X 2,755,978 7/ 1956 Schoenwolf... ..53/248 X 3,351,473 11/1967 Belk ..53/126 X 3 ,403 ,494 10/1968 Livingston ..53/246 5] Mar. 7, 1972 Primary Examiner-Wayne A. Morse, Jr. Attorney-Arthur O. Klein 9 [57 ABSTRACT Apparatus for making propellants of powder strands. A plurality of outer strands of the same length are first placed generally in the form of a bundle in an open-topped vertical receptacle. The bottom end of the receptacle is closed by a plate which may be withdrawn when the strands are to be allowed to fall into a strand-orienting fixture. The fixture is placed beneath the receptacle in alignment therewith, the fixture having a multiperforated upper plate with vertical, funnel-shaped openings therethrough which receive the lower ends of the strands therein when the combination of receptacle and fixture are vibrated, whereby to guide strands through such openings and downwardly into contact with a supporting plate. The powder strands in the embodiment shown are hollow. After all of such openings are closed by the upper ends of the forwarded strands, the receptacle is removed from the fixture, and there is applied to the upper end of the fixture a jig or second fixture carrying a plurality of spaced mandrels, when the strands are hollow, which are introduced into the upper ends of the hollow strands now positioned in the first fixture. The jig is provided with means whereby the mandrels grip the upper ends of the hollow strands sufiiciently to sup port the strands. The second fixture is then removed from the first fixture, and the thus-oriented and supported strands are transported, in very accurately spaced position, for further treatment, such as drying, and ultimately to be introduced into the chamber of an explosive device. When the strands are not hollow, rings or sleeves may be substituted for the mandrels.

l1 Claims,5DrawingFigures PAIENTEH MR 7 I972 SHEET 1 0F 3 Inveniar:

G abr/a 6/205 Wm 01 AiLOrnLy I INVENTOR 7 6 abr 0/ 6/205 ATTORNEY l I l J ll l'lluullill nnnnunnnnnnn'n PAIENTEDMAR 1 1972 PAIENTEUMAR 7 I972 3.647. 200

sum 3 or 3 In van/0r:

GBbf/l/ GRO'S vdmupm Attorney APPARATUS FOR MAKING PROPELLANTS OF POWDER STRANDS The, present invention relates to an apparatus for forming propulsive explosive charges from elementary powder strands having an accurately defined geometric spacing.

It is known that one obtains a more homogeneous and regular combustion of a propulsive explosive charge when it is made up of strands which are regularly spaced in accordance with certain geometrical figures. The attainment of such regular structures presents technical difficulties particularly in cases in which the explosive charges are fabricated in a large number of strands, or when all the strands do not have the same length. The two principal problems posed by the quantity production of explosive charges of the type indicated are concerned, on the one hand, with the placing of the strands in the strand-positioning fixtures, and on the other hand, the locking of the thus-oriented strands so as to preserve their regular geometric shape during the course of later manufacturing operations.

The invention described hereinafter has for its object the provision of new solutions to such manufacturing problems by permitting a great regularity of structure of the spaced strands to be achieved while increasing the rapidity of manufacture as well. In particular, it permits the facile manipulation of the structures produced during the different subsequent phases of the manufacturing operations. v

The present invention relates to an apparatus for achieving such results; such apparatus puts the powder strands in place and then locks them in such predetermined spaced relationship, wherein the strands are positioned according to a regular geometric shape.

The apparatus of the invention has three principal parts, the first of which serves more particularly in the initial placement of the powder strands, the second of which serves to space the strands very accurately after leaving the first part of the apparatus, and the third of which locks the strands in place.

The first part principally comprises a cylindrical receptacle, a movable closure member for the lower end of the receptacle, and a strand-dividing plate or grill. The receptacle is of circular cylindrical shape having an interior section which is appropriate for the section of the structure which is being made. The movable closure member is located at the bottom of the receptacle, and maintains the lower ends of the powder strands in the same plane prior to the introduction of the strands into the strand-spacing fixture positioned beneath the receptacle. The strand-separating grill is in the form of a disc coaxial of the receptacle, the portion of the disc underlying the space in the receptacle is provided with a plurality of spaced vertical passages therethrough. Such passages are of bellmouthed shape, the radius of each passage immediately below the closure device for the receptacle substantially exceeds the radius of the passage at the lower end thereof.

The second part of the apparatus is a first fixture, disposed beneath the receptacle, for receiving the powder strands from the receptacle. When the first two main parts of the apparatus are assembled, the lower ends of the passages in the grill of the first part immediately confront and are aligned with strandreceiving passages at the top of the first, strand-positioning fixture.

The third part of the apparatus is a second fixture which serves more especially to lock the strands in positioning guides provided in the first, strand-positioning fixture. It includes a plate, a means for centering the plate, and eccentric means for locking the plate. The'plate is in the form of a disc-carrying shafts or rings, each shaft or ring being situated confronting a positioning hole of a strand-positioning means and having a fonn and dimensions appropriate to those of the strands (shafts or rings being employed depending upon whether the hollow outer strands are to be engaged interiorly or exteriorly). The plate carries the pilot pin for positioning it with respect to the said first fixture. The means for centering the positioning means with respect to the strand-positioning fixture, for example, a ring, assures the guiding of the plate upon its introduction at the end of the first, positioning fixture. An eccentric selectively displaces the plate with respect to the positioning fixture, causing the outer strands to be gripped between the shafts or rings and the positioning fixture. There is thus provided a strand-locking or blocking means which maintains the strands gripped and spaced during the course of subsequent manipulations of the strands.

The various parts of the apparatus may be made of different appropriate materials; one may use advantageously light altoys, bronze, or thermoplastic or thermohardening plastic materials.

The following description, and the drawings annexed hereto and forming part of this application, describe and illustrate a nonlimiting embodiment of the apparatus and will render the invention more readily understood.

In such drawings:

FIG. 1 is a view in elevation of the combination of strand supplying means and strand-positioning means, the remainder of the apparatus is shown only generally;

FIG. 2 is somewhat schematic view of the apparatus of FIG. 1, the strand-receiving receptacle and the strand-dividing or spacing means associated therewith being shown in vertical diametral section, there is being shown mounted beneath such receptacle a fragmentarily illustrated first fixture for positioning the strands, certain of the parts being shown in elevation;

FIG. 3 is a view in plan of the upper strand-positioning plate of the first fixture;

FIG. 4 is a view partially in vertical transverse section and partially in elevation of a fixture to be applied to the upper end of the first, strand-positioning fixture after the latter fixture has been filled with strands; and

FIG. 5 is a fragmentary view, partially in transverse section and partially in elevation, of the upper end of the first, strandpositioning fixture and of the second, strand-locking fixture which has been applied to the first fixture.

In FIG. 1 there is shown a receptacle 10, a retractable, strand-supporting plate 20 at the lower end of the receptacle, a strand-dividing plate or grill 30 below the closure plate 20, and a first, strand-positioning fixture, generally designated 40,

disposed beneath receptacle 10. The strand-positioning fix-' ture 40 is made up of three vertically spaced horizontal plates 42, 44, and 45, each of such plates being provided with a plurality of strand-receiving passages therethrough, the respective passages in the plates 42, 44, and 45 being aligned and so disposed as to hold the strands in the predetermined desired geometrical position. The fixture 40 is supported upon a member 46 having a flat upper surface, member 46 being fixedly secured to the bed of the machine. The horizontal plates of the fixture 40 are secured to a plurality of vertical rods 43 (two shown), the lower ends of rods 43 being sharpened to a conical configuration and fitting in conical recesses in the upper surface of the member 46.

As shown in FIG. 2, the receptacle 10, which is in the form of a vertical sleeve having radially spaced inner and outer walls, the inner wall being designated 12, has a frustoconical configuration 11 at the upper end thereof leading into the space within the sleeve 10. Initially the closure plate 20 is thrust inwardly into the position thereof shown in FIG. 1 so as completely to underlie the opening in the receptacle 10. The strand-dividing plate 30 is disposed below and secured to the receptacle 10, the closure plate 20 being disposed between the upper surface 33 of the dividing plate 30 and the lower end of the chamber in the receptacle 10. The dividingplate 30 has a plurality of vertical openings 31 therethrough, the openings 31 being funnel shaped, the upper ends of the openings having a diameter markedly exceeding the diameter of the lower end thereof. The hollow powder strands are placed within the receptacle [0 in vertical position in the form of bundles until the receptacle is roughly filled. The closure plate 20 is now withdrawn so as to open the lower end of the receptacle l0 completely, and to permit the lower ends of the outer strands l to enter the passages 31. The receptacle l0 and the fixture 40 are preferably vibrated or otherwise subjected to mechanisal shock, whereby to ensure that the powder strands 1 will enter each of the passages 31. Upon the retraction of plate 40, the powder strands now pass downwardly into the strand-positioning fixture 40, vibration of such fixture aiding the position- :ng of the strands. The machine upon which the receptacle l snd fixture 40 are mounted is preferably provided with a suitable vibrating means (not shown) to vibrate both the receptacle l0 and the fixture 40.

The vertical holes 41 in the upper plate 42 of the fixture 40 are aligned with and are of generally the same radius as the lower ends of the passages 31 in the dividing plate 30. After the outer strands l have fallen into the position shown in phantom lines in FIG. 2, the receptacle 1 and the dividing plate 30 are removed from the fixture 40, carrying with them the plate 20. It will be seen that the strands l resting upon the member 46 have their upper ends held very accurately in a desired pattern by the walls of the holes 41 in plate 42 through which they pass. The intermediate and lower ends of the powder strands are similarly accurately held and spaced by the holes in plates 44 and 45 through which they pass. in the illustrative apparatus shown, as can be seen in FIG. 3, the passages 41 in the plate 42 are disposed equally linearly spaced in successive concentric circles. In some instances it is sufficient that the powder strands be held at plate 42; in that case, plates M and 45 can be replaced by rings through which the powder strands pass freely.

in order to lock the powder strands l, which are now disposed in the first, strand-positioning fixture 40, a second, locking fixture 70 shown in FIG. 4 is applied to the first fixture m the manner shown in PK}. 5. The second, locking fixture has an upper plate 50 which is provided with a plurality of passages 51 therethrough spaced in the same manner as the passages 41 in plate 42, there being a plurality of mandrels 54 secured to plate 50, one at each opening 51. The second fixture, as shown in FIG. 5, has a shallow groove 53 in its periphery, groove 53 having an upper end wall 52. An outer, spacer band 60 is disposed in such groove, the upper edge of the band 60 being placed in abutment with the shoulder 52. The band 60 serves to space the plate 50 from the upper surface of the plate 42, the lower edge of band 60 engaging the edge of the upper surface of plate 42, as shown in F IG. 5. Plate 42 is provided with a vertical, tapped hole 79 which threadedly receives the lower end 81 of a thumbscrew 80 having a thumb wheel 82 on the upper end thereof. Diametrically opposed to the thumbscrew 80 on plate 50 is a rodlike member 72 which is joumaled in a vertical bore in the plate 50. The upper end of the member 72 is provided with a cross handle 71, whereby the member 72 may be rotated. The lower end of the body 61 of the member 72 is provided with a pilot pin 73 of smaller diameter than the main body 61 of the member 72, the pilot pin 73 being disposed eccentrically with respect to the axis of the main body 61 of member 72. The main body 61 isjoumaled in a bore in place 50. The plate 42 is provided at a location diametrically opposed to the hole 79 with a first hole 56 receiving the pilot pin portion 73 of member 72 and a second, larger bore 57 which is disposed eccentrically of the bore 56 and accurately receives the body 61 of the member 72.

The second fixture is first presented to the first fixture with the body 72 turned so that both the main body thereof and the pilot pin portion 73 thereof readily enter the respective bores 57 and 56 when screw 81 is coaxial of the hole 79. The lower ends of the mandrels 54, which are of a diameter only slightly less than the inner diameter of the powder strands 1, freely enter the respectively upper ends of such strands. The thumbscrew 80 is now tightened. The body 72 is now swung about its axis by the lever handle 71, the plate 50 of the second fixture and the mandrels 54 secured thereto being swung out of alignment with their initial position. so that the mandrels 54 thrust the upper ends of the powder strands sidewardly into gripping engagement with the walls of the passages 41 through the plate 42. The first and second fixtures, secured together as shown in FlG. 5. may then be moved with the upper ends of the powder strands 1 secured thereby; one may then conduct subsequent operations upon the thus-held strands, such as drymg, the connection of the extremities of the strands by a sole, and the storage of the strands.

it will be understood that the present invention is not limited to the above-described embodiment, but is intended to embrace all variations conforming to the spirit of the inven- [iOI], in particular, all the different operations such as the putting in place or the removal of the storage container 10, the locking operation of the eccentric 72, 73, and the operation of the closure means 20. These may be carried out with the aid of various means which may be mechanically, pneumatically, hydraulically or electrically operated.

Although the invention is illustrated and described with reference to one preferred embodiment thereof, it is to be expressly understood that it is in no way limited to the disclosure of such a preferred embodiment, but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. An apparatus for arranging a plurality of self-sustaining powder strands in spaced parallel relationship in a predetermined pattern, comprising a receptacle having a vertical cylindrical space therewithin adapted to receive a vertical bundle of strands, means selectively opening and closing the bottom of the receptacle, means below the last-named means for dividing and spacing the strands as the strands fall therethrough, and a strand-receiving fixture below the stranddividing means for holding the strands in their thus-spaced positions.

.2. An apparatus according to claim 1, wherein the means for opening and closing the receptacle comprises a plate slidable beneath the lower end of the receptacle.

.3. An apparatus according to claim 2, wherein the stranddividing and spacing means comprises a multiperforated plate member disposed beneath the slidable plate and spanning the opening through the lower end of the receptacle, the perforations in said plate member being passages accurately receiving the strands, said passages being spaced in said predetennined desired pattern.

4. An apparatus according to claim 3, wherein the said passages are frustoconical in shape and converge downwardly, the lower ends of the passages accurately receiving the strands.

.5. An apparatus according to claim 3, comprising means to subject the receptacle and the strand-receiving fixture to vibrations, whereby to facilitate entry of the strands into the passages in the strand-dividing plate member and the strandreceiving fixture when the receptacle closing plate is withdrawn.

6. An apparatus according to claim 3, wherein the strandreceiving fixture has a second plate member which is disposed immediately beneath the first plate member, the second plate member having a plurality of holes therein coaxial of the passages through the first plate member, said holes accurately receiving and positioning the strands.

7. An apparatus according to claim 1, comprising selectively operated means for gripping and retaining the strands in the strand-receiving fixture.

B. An apparatus according to claim 7, wherein the strandgripping and retaining means comprises a second fixture selectively mountable on the first fixture after removal of the receptacle, said second fixture having means cooperating with the first fixture to grip the upper ends of the strands.

9. An apparatus according to claim 8, wherein the strands are hollow, the second fixture includes a mounting plate and mandrels thereon introducible into the upper ends of the strands in the first fixture, and means to displace the mounting plate sidewardly with respect to the plate member of the first fixture so as to grip the strands between the mandrels and the sidewalls of the passages in said plate member.

M). An apparatus according to claim 9, comprising means .releasably to secure one end of the mounting plate to the plate member of the first fixture for pivotal movement with respect 3 64 7 2 O 5 6 thereto, and eccentric means disposed to interact with the other ends of the mounting plate and the plate member of the first fixture to displace the mounting plate sidewardly.

11. An apparatus according to claim 1, wherein the strands are powder strands to be used in making propellants. 5 

1. An apparatus for arranging a plurality of self-sustaining powder strands in spaced parallel relationship in a predetermined pattern, comprising a receptacle having a vertical cylindrical space therewithin adapted to receive a vertical bundle of strands, means selectively opening and closing the bottom of the receptacle, means below the last-named means for dividing and spacing the strands as the strands fall therethrough, and a strand-receiving fixture below the strand-dividing means for holding the strands in their thus-spaced positions.
 2. An apparatus according to claim 1, wherein the means for opening and closing the receptacle comprises a plate slidable beneath the lower end of the receptacle.
 3. An apparatus according to claim 2, wherein the strand-dividing and spacing means comprises a multiperforated plate member disposed beneath the slidable plate and spanning the opening through the lower end of the receptacle, the perforations in said plate member being passages accurately receiving the strands, said passages being spaced in said predetermined desired pattern.
 4. An apparatus according to claim 3, wherein the said passages are frustoconical in shape and converge downwardly, the lower ends of the passages accurately receiving the strands.
 5. An apparatus according to claim 3, comprising means to subject the receptacle and the strand-receiving fixture to vibrations, whereby to facilitate entry of the strands into the passages in the strand-dividing plate member and the strand-receiving fixture when the receptacle closing plate is withdrawn.
 6. An apparatus according to claim 3, wherein the strand-receiving fixture has a second plate member which is disposed immediately beneath the first plate member, the second plate member having a plurality of holes therein coaxial of the passages through the first plate member, said holes accurately receiving and positioning the strands.
 7. An apparatus according to claim 1, comprising selectively operated means for gripping and retaining the strands in the strand-receiving fixture.
 8. An apparatus according to claim 7, wherein the strand-gripping and retaining means comprises a second fixture selectively mountable on the first fixture after removal of the receptacle, said second fixture having means cooperating with the first fixture to grip the upper ends of the strands.
 9. An apparatus according to claim 8, wherein the strands are hollow, the second fixture includes a mounting plate and mandrels thereon introducible into the upper ends of the strands in the first fixture, and means to displace the mounting plate sidewardly with respect to the plate member of the first fixture so as to grip the strands between the mandrels and the sidewalls of the passages in said plate member.
 10. An apparatus according to claim 9, comprising means releasably to secure one end of the mounting plate to the plate member of the first fixture for pivotal movement with respect thereto, and eccentric means disposed to interact with the other ends of the mounting plate and the plate member of the first fixture to displace the mounting plate sidewardly.
 11. An apparatus according to claim 1, wherein the strands are powder strands to be used in making propellants. 